# PWM with SG3525

Hi, could anyone help me with SG3525? I have a PWM circuit with SG3525 and need to modify the circuit so that I can get ~0.2 Hz cycle
period. This is very slow compared to most of the circuits that I can get. Probably, I can change the frequency by changing the capacitor or resistor at Rt and Ct (pin 5 and 6), but I don't know the equation to calculate those. Please help me!!!
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According to the datasheet, approximate oscillator frequency is defined by :
f = 1/(CT*(0.7*RT + 3*RD))
http://www.st.com/stonline/books/pdf/docs/4286.pdf
-- Shawn
face=Arial size=2>...</FONT></DIV><FONT face=Arial size=2>&gt; Hi, could anyone help me with SG3525?&nbsp; I have a PWM circuit with<BR>&gt; SG3525 and need to modify the circuit so that I can get ~0.2 Hz cycle<BR>&gt; period.&nbsp; This is very slow compared to most of the circuits that I can<BR>&gt; get.<BR>&gt; Probably, I can change the frequency by changing the capacitor or<BR>&gt; resistor at Rt and Ct (pin 5 and 6), but I don't know the equation to<BR>&gt; calculate those.<BR>&gt; Please help me!!!</FONT></BODY></HTML>
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